Subtract 18/7 from 81/72
1st number: 1 9/72, 2nd number: 2 4/7
81/72 - 18/7 is -81/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 7 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
81/72 = 81 × 7/72 × 7 = 567/504 - Likewise, for the 2nd fraction, since 7 × 72 = 504,
18/7 = 18 × 72/7 × 72 = 1296/504 - Subtract the two like fractions:
567/504 - 1296/504 = 567 - 1296/504 = -729/504 - After reducing the fraction, the answer is -81/56
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